Process for producing closed-end tubular bodies



Aprifi 28, 1931. slNGER 1 3@2,843

PROCESS FOR PRODUCING CLOSED END TUBULAR BODIES Filed 001',- lO, 1927 2 Sheets-Sheet 1 Fig.1

. g v k X f PRQCESS FOR PRODUCING CLOSED END TUBULAR BODIES Filed Oct. 10, 1927 2 Sheets-Sheet 2 I Patented Apr. 28, 19.3 1

FFlc FRIEQZ SING-E11,, F NUREMBERG, GERMANY PROCESS FOR PZ RdDUGING CLOSED-END TUBULAR BODIES Application filed October 10, 1927, Serial No. 225,878, and in Germany June 12, 1986..

My invention pertains to processes for producing closed end tubular bodies having reinforcements or enlargements at the open ends thereof, and has as its object to provide a method by'which such articles, of a high quality, may be made more easily, quickly and economically than has heretofore been possible.

In carrying out my invention,- 1 provide preliminaril a blank which is formed, at one end, witl ia reinforcement of any desired shape,as, for instance, with a flan e, cone, or the like,and then extrude suc blank so that the reinforcement is around the open end of the extruded article.

In order that my invention may be fully understood, 1 have described the same more specifically below in connection with the accompanying drawings, in which:

Fig. l is an axialsection through the extruding tool with the metal blank, having the desired reinforcementthereon, to be extruded in place therein Fl 2 shows the same parts after the entrusion as been completed; and

. Fig. 3 is an illustration of press adaptedfor edecting the extrusion operation.

Referring to said drawings, a is the bed plate of a crank press of the geared or plain 39 type. Gnto this plate is clamped, by means of the clamping ring 7%: and the screws Z, the

lower part of the tool which comprises the hardened steel-plate h,the die a, and bushing d. e denotes the punch, the lower part f of which is attached to the plunger m of the press (Fig; 3). A cog-wheel 0 which is affixed to the crank shaft n is driven by a direct current adjustable speed motor in by the intermedia of a change-s eed gear q, r, s, t. Sai motor makes a out 1260? revolutions in a minute in either direction, but when the punch e bears upon the blank h to he extruded and the pressing resistance becomes active, also four current-guards be- 45 come active in correspondence with the increase of the pressure and reduce the speed of the motor down to 336 revolutions per ,minute, the turning moment increasing in the same proportion. Y The method is carried through in this way,

that first the bottom part of the tool and the punchis preheated a propriately with a gasburner, whereaftent e punch and thatmem- 'ber of'the tool which is to receive the metal piece to be extruded is coated with a mixture of graphite and oil. The blank hotv steel or other metal to be extruded, having thereonthe reinforcement to be described below,

is withdrawn from the furnace, quickly freed from the adhering scale and instantly placed an into the die. Immediately thereafter the motor is started by the push-button control, the punch is forced into the blank and this latter is extruded between the punch and the bushing, as shown in Fig. 2. The extruding as process havingbeen efiected, the punch with the hollow body thereon is withdrawn from the matrix and the hollow body stripped 0d the punch by known means.

' The blank it to be extruded is provided to with a preliminarily formed flange reinforced by a conical transition member, the whole a being, however, integral, as shown in Fig. 1.

Hollow bodies whichiare to have a fiange of this or similar shape, that is to say, with re a reinforcement, cannot be made by providing the bushing at its upper end with a corresponding enlargement, except when the flange is to be very small, in that the extruded etal tends very little to expand laterally so as to an fill up said enlargement of the matrix. llf the, flange, especially with a conical or similar section, as shown, is to be comparatively large it must be forged preliminarily and "the flange bearing end of the metal piece must to project over the bushing, as in Fig. 1. The formation of the flange may form a separate working step, the metal piece being, of course, sulliciently hot, but the formation of the flange and thereafter the extrusion of the metal piece may be carried through in the same'press' and with the same die, there beingthen-used, however, two punches, one

jc'or the forging phase, and the other for the extruding phase.

By the above described method,.it is possible to produce closed end tubular bodies and hollow vessels, having reinforcements at the open ends thereof, from steel and other low metals and alloys, very easily and economioally and of a superior quality.

I claim:

The method of manufacturing closed end tubular articles and hollow metal bodies provided with a reinforcement of any desired shape at the open end, consisting in the steps of first forging said end so as to provide the respective hol ow body thereby with the reinforcement, and then extruding the thus prepared body.

In testimony whereof I have afiixed my signature. FRITZ SINGER. 

